I recently tried a different shaft in my M2 driver and shortly after replacing the original shaft, the head started to rattle.  I removed the shaft and could see the fastening screw/bolt and what looks like a small washer type ring on the end of the bolt.  When I shake the head, it sounds exactly like it does when the shaft is attached.  I made sure the shaft was torqued down with the supplied wrench.  Is there anything that be done to eliminated the rattle?